Estuary Fish Inventory Network – About

In 2006, a sampling procedure was established by the Ministère des Forêts, de la Faune et des Parcs for the gathering of reproducible quantitative and qualitative data aimed at developing a fish monitoring network for the St. Lawrence Estuary. After three years to standardize the method (2006-2008), the Estuary Fish Inventory Network (EFIN) was established. These official data were produced as part of the St. Lawrence Action Plan 2011-2026.

Since 2009, annual monitoring of the estuary fish population has taken place at four different experimental fishing sites located on both the north and south shores (see map). Two of these stations are located in the middle estuary, at Rivière-Ouelle and Sainte-Irénée, the other two in the fluvial estuary in Cap-Santé and St. Nicolas. All sampling operations of the St. Nicolas station fall under the responsibility of the Aquarium du Québec.


The St. Lawrence Estuary Fish Inventory Network provides an updated picture of the dynamics of fish populations encountered in the fluvial and middle estuaries. The implementation of the EFIN ensures the annual harvest of a large number of data used to:

  • determine the composition of fish communities present in the estuary (diversity);
  • assess the relative abundance of species of interest (CPUE);
  • assess the size and age structures of species of commercial and sportfishing interests;
  • determine the strength of the cohorts;
  • assess fish health (e.g., the presence of anomalies, detection of toxic substances);
  • assess the dynamics of fish populations.